Molded fibrous pulp container having closure securing means



H. R. DENTON April 1, 1947.

MOLDED FIBROUS PULP CONTAINER HAVING CLOSURE SECURING MEANS Filed March 5l, 1944 2 Sheets-Sheet l www INVENTOR. Ha/evy A. DENTo/v HTTONE YS April 1, 1947. H. R. BENTON 2,418,248

MOLDED FIBROUS PULP CONTAINER HAVING CLOSURE? SECURING MEANS Filed Marc'h 5l, 1944 2 Sheets-Sheec 2 r\\\\\mes 24 ai Z7 I N VEN TOR. H/Mvy I?. DEA/70N BY A @74%, Wim@ HTTORNEYJ,

Patented Apr. 1, 1947 MOLDED FIBROUS PULP CONTAINER HAV- ING CLOSURE SECURING MEANS Harvey R. Benton, Gakland, Calif., assigner to Moist-R-Proof Container Co., San Francisco, Calif., a corporation of California Application March 31, 194i-, serial No. 528,902

'Ihis invention relates to containers :and has for one of its objects the provision of a polygonalsided container with a closure releasably secured thereto. for closing an open topand which container, closure, and locking or closure-securingmeans are so constructedas to cooperate with each other for forming a tightly closed container that becomes even more tightly closed upon outward expansion of the contents against the side walls.

Another object of the invention is the provision of a container that is molded from fibrous pu`p material, such as papier-mch, and the walls of which and the closure are slightly oompressible and resilient and are so constructed as to utilize these characteristics in automatically providing a tight seal between the closure and side walls in engagement therewith upon expansion of the contents of the container irrespective of irregularities in the engaging surfaces of the closure and side walls.

A stil1 further invention is the provision of an improved molded container that is not subject to breakage or distortion upon severe usage and that will protect the contents thereof during such usage.

An additional object is the provision of an improved closure and container structure, both the container and closure having heat insulation properties and being molded from brous'material, and relatively soft, yet strong, and which closure automatically locks on the container and resists removal under severe handling and is particularly suitable for frozen foods by the heat insulation properties thereof and in that air spaces between stacks and tiers of such containers are eliminated.

Other objects and advantages will appear in the description and drawings.

In the drawings,

Fig. 1 is a Dart sectional, part elevational view of one form of the invention.

Fig. 2 is a` sectional view taken along line 2-2 of Fig. i.

Figs. 3 to 5, respectively, are part sectional, part elevational views of several different forms of the invention.

Before describing the invention in detail it is to be understood that it i-s particularly for polygonal sided containers such. as oblong, square, hexagonal or triangular in horizontal cross-sectional contour with a closure and bottom4 at its upper and lower ends respectively. Also the containers of this invention are preferably molded from brous` pulpyV material. One excellent material 3` Claims. (Cl. 2.29-45i is. papier-mch for the reason that it is cheap andv walls, etc., formed therefrom are quite strong and are somewhat compressible and resilient. Also waterprooiing or astiffening medium can beV incorporated in the pulpy material for making the containers and closures therefor waterproof or relatively stiifer than. would otherwise be the case, although` stiffness 0r hardness to the point of brittleness is not desirable.

In detail, referring to Figs. 1, 2, the container comprises lateral sides l and a bottom 2 integrally.y molded from a fibrous pulp material.

The. upper side of the container is open and a ciosure t. is provided! therefor, which closure is' f preferably of the same material as4 that of they container and is formed with lianges 4 molded integrally therewith and depending from its edge-s for overlying the upper marginal portionsof the side walls t when the closureis substantially against the free upper edges of said side walls.

Equally spaced from the upper edges of sidel walls i are grooves or outwardly opening recesses 5. These recesses are one to each side and preferably extend completely :across the latter to joining relation with each other at the corners of the container. The forming of such groove or recess may result in a projection, rib or ridge B that is aligned with each recess and that projects inwardly into the container from the inner side of each-wall l'. These ribs are respectively generally convex in cross-sectional surface contour and complementary to the generally concave crosssectional contour ofl each recess. This structure contributes to the rigidity of the side walls.

The flanges li" are each formedwith an inwardly projecting rib l that is complementary to each recess 5` and each such rib T is positioned so as to fit in, each recess 5 when the closure is on the container and is substantially resting on the upper edges of the side walls I. The cross-sectionalcontour of each recess 5 transversely thereof is preferably similar to a channel in which the opposite sides extend divergently from the base or bottom thereof'. As each rib lis complementary thereto, it will be seen that once theJ ribs 1 are in the recesses the ribs will seat themselves centrally in said recesses.

Each rib l terminates at its ends at points spaced. from, the ends-of each flange. The ends of such ribs preferablyl gradually merge into the flange asindicated at 8: (Fig. 2). This termina-- tion of; the ribs short ofi the endsof the anges is quite important in` all forms. of the invention since itpermits the. positioning of: the closure on the container.

In operation, upon slightly forcing the sides I inwardly, as by applying slight pressure to said sides toward the center, the flanges 4 will readily slide over the upper marginal portions of the sides until the ribs I snap into recesses 5, at which time the cover is substantially resting on the free edges of side walls I. The cover or closure can only be removed by again forcing the upper marginal portions of sides I inwardly to release the ribs 1 from recesses or by tearing the closure. The cross-sectional contours of the recesses and ribs l, as described, contributes toward drawing the closure downwardly at all times in the event any outward pressure from inside the container should tend to force it upwardly, but as such outward pressure from inside the container is also applied against the side walls I, the closure is more tightly held to the container with any inafiia crease in outward pressure against walls I from inside the container.

In the form shown in Figs. 1, 2 I also provide an additional rib I0 on each wall I spaced below and parallel with the rib 6 that is on the same wall, Ribs III project inwardly into the container and also function to brace the walls, but in addition, such ribs serve as means for retaining a retainer sheet I I in the container below such ribs.

Each retainer sheetI II may be apertured at I2 to receive therein a portion of one of the objects to be held in the container, such as one of the bottles I3 (in dot-dash lines) and to space such bottles from each other and from the container walls. A specially molded base sheet I l may be provided with recesses I5 respectively in coaxial alignment with each opening I2 for the base of each bottle, and which recesses may have concentric corrugations I6 therein for cushioning each bottle against shock.

The sheet II is rectangular or of substantially the same outline as that defined by the walls I, and is relieved along its edges at the corners of the sheet from points I'I (Fig, 2) so as to permit sufficient yielding of the opposite edges of said sheet for passing the ribs I0 to positions below the latter, after which the ribs I0 will prevent the sheet from coming out. The marginal portions I8 of sheet II may extend slantingly downwardly and inwardly toward the center of the container from their free edges, which structure will further contribute toward preoluding accidental upward dislodgment of sheet II from its position below ridge I.

In some instances the ridge 5 may function to hold the sheet II or any other retainer sheet of the same general edge outline in position below such ridge, as indicated in Fig. 4, in which the retainer sheet is generally designated 20. The retainer sheetA II and base sheet I4 are preferably molded from practically the same material as the walls I and have substantially the same characteristics of compressibility and yieldability, yet sufficient rigidity to withstand 0bjectionable accidental distortion upon rough handling of the loaded or filled container.

The containers of Figs. 3 to 5 are adapted for use in the same manner as the containers of Figs. 1, 2 and they have the additional feature of being particularly suitable for frozen foods.

Where more or less liquid foods are frozen the freezing is done after the containers are lled with the food. Heretofore considerable difficulty has been experienced in that the swelling of the contents upon freezing has dislodged the closures or has resulted in other injury to the containers. Also such containers as cylindrical ones or those having beads or ridges projecting ,outwardly from their outer surfaces have provided air spaces or passageways between the containers, and in the event of possible insufficient refrigeration the circulation of air between the containers, such as those packed in storage rooms or in cars, has resulted in spoilage of entire shipments.

The containers of Figs. 3 to 5 have no projections on their outer sides and can therefore be tightly packed together completely occluding air circulation between adjacent containers in a shipment, Thus a plurality of closely packed stacks and tiers of such containers having frozen foods therein would virtually be a solid block of frozen material and accidental defrosting thereof could only occur gradually from the outermost layer inwardly, whereby in practically every case there would only be a likelihood of spoilage occurring in the outermost layer before the lack of adequate refrigeration were discovered or corrected. The remainder of the shipment would remain frozen.

In the form of invention illustrated in Fig. 3 an outwardly opening recess 2I may be formed :in the upper marginal portion 22 of each side wall 23 of the container, which marginal portion is oiset inwardly in each wall relative to the center of the container a distance substantially equal to the thickness of the depending flange 24 of c1osure 25, The recess 2l in each such portion is preferably spaced between the upper and lower edges of each marginal portion, and extends the full width of each side wall the same as recess 5 in Figs. 1, 2.

The recess 2l may be concave and curved in cross-sectional contour if desired, or it may be of the contour of recess 5 as is indicated in Figs. 1 and Ll.

Each flange 24 is of a width substantially equal to the width of each marginal portion 22, and an inwardly projecting rib 26 having substantially the same contour as that of recess 2|, but convex instead of concave, is positioned to i-lt in each recess when the closure is substantially supported on the upper free edges of portions 22. The ribs 26 terminate short of the ends of the flanges 24 at points 2l' in the same manner as ribs 1 of flanges 4, and for the same reason.

The provision of ribs 26 being spaced from the lower f-ree edges of flanges 24 insures a seal between the flat surfaces of the flanges and marginal portions 22 both above and below ribs 26 and recesses 2l, and also the free edges of flanges 24 are substantially against the shoulders 28 where marginal portions 22 join the main walls 23 that are therebelow, thus giving additional sealing protection.

The outer surfaces of each flange 24 and wall 23 are coplanar and there are no recesses or projections above or below the top 25 or the bottom of the container opposed thereto, hence a very tight solid pack of such'containers vcan be made.

In Fig. 4 the same general `structure is shown as in Fig. 3 except that the ribs 3!! on flanges 3| and the recesses 32 on inwardly offset marginal portions 33 of sides 34 are not curved in crosssectional contour, but instead the sides of the recesses 32 are flat and extend divergenty while the sides of ribs 3Q that engage the sides of each in the form of the device shown in Fig. 4, although where there is a depression as in Fig. 3, the fact that this depression does not extend to the ends of the flanges prevents there being any objection to its presence since air cannot circulate between packages.

In certain instances it may be desirable for the inner sides of the packages or containers as well as the outer sides to be coplanar in every dimension, and in Fig. 5 I show a Structure that is the same as that of Fig. 4 in every respect except that the walls 40 are sufficiently thick to provide the necessary offset in its upper marginal portion 4l without making a shoulder inside the container. The rib 42 that fits in recess 43 in said marginal portion is the same as rib 30 and recess 32 of Fig. 4.

The fact that the containers and closures in all forms of the invention are molded from fibrous pulp material, and which material preferably has a certain amount of compressibility as occurs in papier-mch, is quite benecial in the presentv instance since the compres'sibility of the material insures a tight t of the ribs on the anges in the recesses in the upper marginal portions of the container irrespective of any slight irregularity in surface contour that may occur. As a tight seal isimportant in most instances, the above advantage is quite important.

The heat insulation properties of papier-mache where such material is used, is very beneficial in the case of frozen foods and this combined with the sealing advantages and the contour of the containers, particularly those of Figs. 3 to 5, provides an ideal frozen food container that is economical to make.

The drawings and description are not intended to be restrictive of the invention but are merely illustrative thereof.

Having described the invention, I claim:

1. A molded four-sided container having rectangular side walls and an open upper side, each of said four side walls being formed with a horizontally extending inwardly projecting rib at the same distance from said upper side,.a rectangular horizontally disposed retainer sheet of relatively resilient material within said container and positioned below said ribs, said sheet being relieved for a predetermined distance from each of its corners and for a width about equal to the thickness of each of said ribs and the remainder of the sheet along its edges and between the relieved portions extending below the said ribs respectively.

2. A molded four-sided container having rectangular side walls and an open upper side, each y of said four side walls being formed with a hori- Zontally extending inwardly projecting rib at the same distance from said upper side, a rectangular horizontally disposed retainer sheet of relatively resilient material within said container and positioned below said ribs, said sheet being relieved for a predetermined distance from each of its corners and for a width about equal to the thickness of each of said ribs and the remainder of the sheet along its edges and between the relieved portions extending below the said ribs respectively, a molded rectangular cover for said open side including depending flanges at its edges adapted to extend over the outer surfaces of the upper marginal portions of the side walls, a rib projecting inwardly from each -of said flanges,

' and an outwardly opening recess formed in each of said side walls adapted to frictionally receive each of said ribs therein in interlocking relationship.

3. A molded four-sided container having rectangular side walls and an open upper side, each of said side Walls being formed with an outwardly opening recess in the outer surface thereof and a correspondingly positioned complementarily formed rib projecting inwardly into the container from the inner surface thereof, a rectangular retainer removably and frictionally held within the container below said rib and by the latter, a rectangular molded cover for said open side having a flange along each side depending therefrom and a rib projecting from the inner side of each flange respectively removably and frictionally held in each of said recesses.

HARVEY R. DENTON.

REFERENCES CITED The following references are of record in 'the le of this patent:

UNITED STATES PATENTS Number Name Date 2,120,905 Moore June 14, 1938 1,417,707 Wright May 30, 1922 2,203,955 Frederick June 11, 1940 2,230,877 Aument Feb. 4, 1941 2,269,785 Rigerman Jan. 13, 1942 FOREIGN PATENTS Number Country Date 146,143 Swiss Mar. 31, 1931 

